Keyword research is as critical to search engine marketing as ever, despite the search engines continually improving their sense of ‘search intent’. There’s no point in focusing on searches that nobody’s making, just as online search made it daft to describe your products by names that customers don’t use (and yes, plenty of manufacturers are still arrogant enough to do this). In 24 Best Google Keyword Planner Alternatives, Search Engine Journal has provided some interesting tools to complement the built-in tool in Google Ads. If you’re working in a specialist market sector, it’s well worth looking at as many data sources as possible, because even the Google Ads Keyword Planner may not have that many suggestions.
The majority of tools nowadays are paid for, but many have free trials or limited-use options which may be sufficient for occasional use. And don’t forget to get all the information you can from your own Google Search Console.